Carlos, whose full name is Carlos Barrios, is a character introduced in the final season of the anime, Dr. Stone: Science Future, during the North American arc. Before the world was petrified, Carlos had a professional career as a race car driver. At the young age of sixteen, he began working for the Wright family as their driver, establishing a long-standing relationship with their daughter, Luna Wright. It was in this capacity that he was present when the first global petrification event occurred. At that moment, he was carrying a platinum ring intended as a gift for Luna and, to keep it safe, he put the ring in his own mouth just before being turned to stone.

After being revived from the stone thousands of years later, Carlos continues to serve and protect Luna. He is a loyal companion to her, often seen alongside her other protector, a man named Max. While Max is described as her bodyguard, Carlos has a long and deep history with her, acting as her steadfast protector and driver. His personality is characterized by his sincere devotion to Luna, which is his primary motivation. He is generally cooperative and, while protective, does not display excessive aggression. When he and Max are discovered by Taiju while on a reconnaissance mission from the enemy scientist Dr. Xeno, Carlos is initially bewildered by the Kingdom of Science's open and friendly nature. He ultimately decides to help them, primarily upon learning that Luna has allied herself with Senku Ishigami. This event highlights that his loyalty is to Luna above any other cause or allegiance.

In the narrative, Carlos’s most significant roles are logistical and supportive. His pre-petrification skill as a professional race car driver proves to be a critical asset to the Kingdom of Science. After he switches sides, he takes over the driving of their science vehicle from the inexperienced Taiju, successfully delivering a vital drilling machine to the front line of a conflict. His knowledge of the enemy's stronghold is also invaluable, as he provides the Kingdom of Science with a hand-drawn map of Dr. Xeno's compound. Another, more subtle, contribution is the platinum ring he protected while petrified. After being revived, this ring becomes a crucial source of platinum, allowing the Kingdom of Science to manufacture essential chemicals for their advanced projects.

Carlos has a few key relationships that define his role. His bond with Luna Wright is the most central; he is smitten with her and has harbored romantic feelings for her for many years. However, upon learning that Luna considers Senku her boyfriend, he accepts her choice and continues to support her selflessly. He also has a long-standing partnership with Max, whom he himself recommended to be Luna's bodyguard, recognizing his own limitations in direct combat compared to his friend. Throughout the story, Carlos demonstrates a very particular set of abilities. He is an exceptionally skilled driver, a talent honed from his years as a professional in a high-performance field. This skill is directly applicable to the new challenges of the stone world. Though not primarily a fighter, he is physically robust. Most importantly, his key ability is his unwavering reliability; he can be counted on to protect those he cares for and to use his unique skills for the group once his trust is earned.